The following shows that Hugues I Magnus comte de Vermandois is my 23rd ggf.
https://www.geni.com/people/Hugues-I-Magnus-comte-de-Vermandois/600...
But when I click up to his father (who is named in the vital dates), the following shows a different lineage: Henry I king of France is my 27th ggf!
https://www.geni.com/people/Henry-I-King-of-France/6000000003645832...
This is not the way the algorithm is supposed to work. It changes to a longer path rather than a shorter one.